1. Field of the Invention
The invention relates to a method for operating installations comprised of chip-card-operated control systems, where the method limits the availability to a properly authenticated control system, and wherein a chip card, provided as storage medium in a control system, makes contact in a receiver device, and exchanges data corresponding to the specific coding of the chip card with the control system via a data bus.
2. Brief Description of the Background of the Invention Including Prior Art
Security methods and the corresponding arrangements furnished for this purpose for chip cards are known in a wide variety. The state of the art is extensively dealt with in the technical literature by Karlheinz Fiesta "Chipkarten: Technik, Sicherheit und Anwendungen", ("Chipcards: Techniques, Security and Applications"): Huethig-Verlag, 1989 on the pages 112-137. The presently available methods for the protection against unauthorized reading, writing and erasing as well as against duplication and simulation are described in this reference.
A limiting of the availability of a chip card is taught in the U.S. Pat. No. 4,808,802 to Kano. In this reference, the limiting refers only to the properly authenticated card owner.
The printed patent document WO 86/04170 teaches the storing of an expiration date into the memory storage of a chip card as part of the personalization method.
The coding possibilities of the last-mentioned method is oriented toward and targets personal identification.
The German Printed Patent Publication DE-OS 3,804,618 to Klaus Lindenschmidt teaches a programmable chip card. The properties of a chip card are mentioned in particular in column 1, lines 34-49. The German Printed Patent Publication DE-OS 3,523,237 to Thomas Krivachi teaches a transporting system for shipping chip cards between two manufacturers. The German Printed Patent DE-OS 3,639,113 teaches an apparatus for reading cards.
However, these known methods are not suitable for providing a solution of the problem posed in connection with the invention. Starting with the consideration to employ the chip card as storage medium for storage programmable controls, it is of understandable significance for the producer of the chip cards and of the control systems to secure the components such that no economic disadvantage can arise for the producer of the chip cards.
A chip card or a chip board card comprises in general microelectronic devices furnished as integrated circuits, memory storage, and the like implanted on a card-like support made of plastic, and wherein the microelectronic devices on the card-like support are connected to each other by an address bus, a data bus, and/or, respectively, by a control bus. The chip card is furnished with contact terminals for electronic interaction with an interface of a control system.